Problem: $\dfrac{7}{5} \div \dfrac{8}{9} = {?}$
Explanation: Dividing by a fraction is the same as multiplying by the reciprocal of the fraction. The reciprocal of $\dfrac{8}{9}$ is $\dfrac{9}{8}$ Therefore: $ \dfrac{7}{5} \div \dfrac{8}{9} = \dfrac{7}{5} \times \dfrac{9}{8} $ $ \phantom{\dfrac{7}{5} \times \dfrac{9}{8}} = \dfrac{7 \times 9}{5 \times 8} $ $ \phantom{\dfrac{7}{5} \times \dfrac{9}{8}} = \dfrac{63}{40} $